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arXiv · 0710.4462

Chemical potential shift induced by double-exchange and polaronic effects in Nd_{1-x}Sr_xMnO_3

K. Ebata·M. Takizawa·K. Maekawa·A. Fujimori·H. Kuwahara·Y. Tomioka·Y. Tokura
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Abstract

We have studied the chemical potential shift as a function of temperature in Nd$_{1-x}$Sr$_x$MnO$_3$ (NSMO) by measurements of core-level photoemission spectra. For ferromagnetic samples ($x=0.4$ and 0.45), we observed an unusually large upward chemical potential shift with decreasing temperature in the low-temperature region of the ferromagnetic metallic (FM) phase. This can be explained by the double-exchange (DE) mechanism if the $e_g$ band is split by dynamical/local Jahn-Teller effect. The shift was suppressed near the Curie temperature ($T_C$), which we attribute to the crossover from the DE to lattice-polaron regimes.

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K. Ebata, M. Takizawa, K. Maekawa, A. Fujimori, H. Kuwahara, Y. Tomioka, Y. Tokura. 2007-10-24. Chemical potential shift induced by double-exchange and polaronic effects in Nd_{1-x}Sr_xMnO_3. https://doi.org/10.1103/physrevb.77.094422

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